This is a long URL but click on it and you'll see okay weapons for cheap prices.
NOW THEN, if you plan to do any heavy contact work, ask your Sensei what he/she uses. I should think tsuba is optional, but ask your instructor. My first bokken had a tsuba and I hated it. It can eat into your skin.
Bujin - http://www.bujindesign.com/
Sei Do Kai Supplies - http://sdksupplies.netfirms.com/index.html
Mushamono - http://www.mushamono.com/musha_home.html
Is another recommended one.
Inexpensive bokkens are fine starting out, but you WILL get what you pay for. Cheap bokkens can and will break... and you don't want to really stab someone during practice, so check around.
ALSO, you can do a search: http://www.aikiweb.com/forums/search.php?
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